1. Field of the Invention
The present invention relates generally to data communication systems and more particularly to repeater devices for regenerating digital signals transmitted through an electronic digital control system.
2. Brief Description of the Prior Art
Various electronic digital control systems are known in the industry which operate to transmit data and commands in order to control a plurality of devices, such as microprocessors, valve actuators, pumps, solenoid valves, printers, memories, and the like. The data and commands which are in the form of a digital signal are transmitted between the corresponding devices over transmission lines in the control system. It is well known that when a number of devices are connected to a transmission line or if the transmission line is very long, signal degradation will occur from the resistive and capacitive effects of the line and devices upon the transmitted signal. Repeaters are oftentimes utilized in the transmission line of such control systems in order to regenerate the signal for retransmission through the system. Generally, the repeaters are required to be placed at specific intervals in the control system depending upon the desired length of transmission of the signal and rate of signal through the system. With digital signal transmission, the speed of the signal through the digital control system is inversely proportional to the distance of signal transmission, i.e., the faster the speed of the signal through the system, the shorter the transmission before signal degradation will occur. As such, many control systems which employ higher rates of signal transmission are not capable of transmitting the signal over long wiring distances without experiencing signal degradation.
There is a need for an improved repeater which will transmit data and commands over extended distances and at high rates of speed through an electronic digital control system.